[PATCH] nvme-pci: set some AMD PCIe downstream storage device to D3 for s2idle

[Limonciello, Mario]

[AMD Official Use Only]

> 
> I guess this happens in one of the amd-pmc driver's system-wide suspend
> callbacks.  Which one?

IIRC it should be caused by:
.suspend_noirq

> 
> > >
> > > In particular, how does it get a chance to run?
> > >
> > > > Since the driver believed that wouldn't happen, the driver did not
> > > > prepare the device for this powerloss event.
> > > >
> > > > It seems that the kernel's assumptions around pm_suspend_via_firmware()
> > > > and pm_suspend_no_platform() may not accurately reflect what the
> > > > platform's firmware actually does.
> > >
> > > Note that this is not about whether or not AML will remove power from
> devices.
> > >
> > > It is about passing control entirely to the platform firmware at the end of the
> > > suspend transition.
> > >
> > > If instead the kernel executes AML that happens to remove power from
> some
> > > devices, that is a totally different case which should not be confused with
> > > the above.
> > >
> > > > I do not know of a better way to detect if the platform will remove power,
> > > > so I'm looking at quirks to suppress PM_SUSPEND_FLAG_NO_PLATFORM
> for
> > > > this platform. I'm hoping there's a better option, though :)
> > >
> > > Honestly, I'm not sure about the clear understanding of what's really going
> on
> > > here.
> > >
> > >
> >
> > We'll discuss internally and come back with a different proposal.
> > Thanks all for your feedback.
> >
> 
> OK
> 
>